Aerodynamic wind propulsion device and method for controlling

ABSTRACT

The invention relates to an aerodynamic wind propulsion device, particularly for watercrafts, comprising an aerodynamic wing being connected to a steering unit by a tractive cable, having a first end of the tractive cable connected to the steering unit and a second end of the tractive cable connected to a base platform, a guiding line having a first end connected to the aerodynamic wing or to the steering unit, a pole being connected to the base platform. According to the invention, an aerodynamic wind propulsion device as mentioned above is provided, characterized in that a second end of the guiding line is connected to the base platform during and between starting and landing maneuvers wherein the guiding line is guided through or along the pole and is capable of transferring a tensile force onto the aerodynamic wing at least during starting or landing.

The invention relates to an aerodynamic wind propulsion device,particularly for watercrafts, comprising an aerodynamic wing beingconnected to a steering unit located below the aerodynamic wing via aplurality of lines, particularly steering lines and/or tractive lines, atractive cable, wherein a first end of the tractive cable beingconnected to the steering unit and a second end of the tractive cablebeing connected to a base platform, the aerodynamic wing having anaerodynamic profile which generates an uplift force in the direction ofthe traction cable when the airflow direction is about perpendicular tothe tractive cable, a guiding line having a first end connected to theaerodynamic wing or to the steering unit, a pole being connected to thebase platform, particularly a mast with a head on top, the pole servingas a docking point for the aerodynamic wing during starting and landing.

A further aspect of the invention is a method for controlling the flightof a wing element for pulling a nautic vessel.

Today, carbon-based fuels like diesel or heavy fuel oil (HFO) are usedas a key resource for propelling nautic vessels. Mostly, diesel enginesare used to provide the driving force for the vessels. With increasingcosts for such carbon-based resources it becomes attractive to applyalternative methods for providing the driving force for nautic vessels.

WO 2005/100147 A1 discloses a positioning device for controlling a wingelement which is connected via a tractive cable to a ship to serve asmain or auxiliary drive. Such propulsion system based on wing elementsflying at high altitude and pulling the ship via a tractive forcerequire large-scale wing elements and the control of such wing elementsis a challenging task. In WO 2005/100147 A1 it is proposed to veer outor haul in the tractive cable in response to the flight condition of thewing element. Whereas by such control mechanism a certain degree offlight control can be achieved it is not sufficient to control the wingelement in all flight conditions, in particular when the wind changesits strength or direction significantly or during starting and landingmanoeuvres of the wing element.

To improve steerability of such wing elements in difficult windconditions it is known from WO 2005/100148 A1 to couple a steering unitclose below the wing element via a number of control lines and toconnect the wing element to the nautic vessel via such steering unit bya tractive cable extending between the nautic vessel and the steeringunit. By this, control of the wing element can be significantly improvedbut it is still a challenging task to control the wing element at lowaltitudes such as during starting and landing procedure.

WO 2005/100149 A1 proposes various sensors to improve control of a wingelement towing a nautic vessel. Whereas these and the former techniquesmay significantly improve the steerability of aerodynamic wing elementsduring regular flight it remains still a quite challenging task tocontrol the wing element at low altitudes, in particular when thestrength and direction of the wind significantly and quickly changes.Loss of control over the wing element however might result in loss ofthe whole system since it is not possible to rescue the system if alarge-scale wing element has come into contact with the water surface.

To improve steerability during starting and landing manoeuvres, WO2005/100150 proposes a telescopic mast erected onto the foredeck of thenautic vessel close to the fixing point of the tractive cable couplingthe wing element to the nautic vessel. Using such mast, the wing elementcan be directly coupled to the top of the mast, thus facilitatingstarting and landing manoeuvres. To achieve engagement between the wingelement and the top of the mast a rudder pendant is slidably coupled tothe tractive cable at one end and connected to the wing element at theother end. This rudder pendant is accessible if the tractive cable hasbeen hauled in so far that the wing element is in low altitude and canbe handled such that it is decoupled from the tractive cable and guidedin such a way as to pull the wing element towards the top of the mast.Whereas such a technique may significantly improve manoeuvrability ofthe wing element during starting and landing procedure if the rudderpendant is decoupled from the tractive cable and guided such that apulling force in the direction of the top of the mast can be applied tothe wing element, it is rather complicated to use and handle the rudderpendant in the course of the starting or landing manoeuvre and failureto couple or decouple the rudder pendant to/from the tractive cable mayresult in failure of the whole system and loss of the wing element.

It is a first object of the present invention to provide a devicefacilitating and improving control of a wing element at starting andlanding manoeuvres.

It is a further object of the invention to provide a device and a methodfor rescuing a wing element in case of sudden loss of lifting force,e.g. due to sudden change of strength and/or direction of the wind.

Still further, it is an object of the invention to provide a deviceimproving and facilitating the control of a wing element at low and highforces acting onto the tractive cable or the wing element.

According to a first aspect of the invention, an aerodynamic windpropulsion device as mentioned above is provided, characterized in thata second end of the guiding line is connected to the base platformduring and between starting and landing manoeuvres wherein the guidingline is guided through or along the pole and is capable of transferringa tensile force onto the aerodynamic wing at least during starting orlanding.

The aerodynamic wind propulsion device according to the inventionprovides a sophisticated set-up for controlling an aerodynamic wing. Thebasic concept of the invention is to provide a continuous guiding linethat is connected to the aerodynamic wing with its one end and connectedto the base platform with its other end. According to the invention thiscontinuous connection is not only provided during starting and landingmanoeuvres but also during a flying phase between starting and landingmanoeuvres.

During starting and landing manoeuvres the aerodynamic wing istransferred from a position close to the pole to a flying position highabove the base platform and vice versa. By providing a continuousguiding line between the base platform and the aerodynamic wing thereaction time to control the aerodynamic wing is reduced, sincedecoupling and transfer of the second end of the guiding line from thetractive cable to the base platform or the mast head is not requiredanymore.

According to the invention the guiding line is guided through or alongthe pole and therefore capable of permanently providing a connectionbetween the aerodynamic wing and the pole, particularly the masthead.According to the invention the guiding line is capable of transferring atensile force directly onto the aerodynamic wing without incorporatingforce transfer via the steering unit. By this, control of theaerodynamic wing can be improved applying this tensile force via theguiding line. By providing a low constant tensile force in the guidingline the reaction time to control the aerodynamic wing is furtherreduced because the tensile force can be increased immediately withouthaving to haul in any slack sections of the guiding line. This directcontrol of the aerodynamic wing provided by the invention is of specialimportance especially for starting and landing manoeuvres, since duringthese manoeuvres there is a high need for controlling the aerodynamicwing. But also during the flying phase between starting and landingmanoeuvres the continuous and permanent connection between the baseplatform and the aerodynamic wing via the guiding line provides asignificant advantage, since on the one hand, the position of theco-flying guiding line can be controlled and twisting of the guidingline for example with the traction cable can be reduced or prevented. Onthe other hand, by providing a continuous connection via the guidingline it is possible to immediately initiate a rescue manoeuvre in caseof an instable situation threatening to lose the aerodynamic wing due tocollapse of the aerodynamic wing and/or watering of the aerodynamicwing.

The guiding of the guiding line through or along the pole is owed to thefact that the starting and landing manoeuvre of the aerodynamic wingusually begins/ends in a position wherein the wing is close to the topof the pole, particularly the masthead, and the steering unit is closeto the foredeck of the vessel. Thus, it is desirable to be able to pullthe aerodynamic wing via the guiding line towards the masthead.

According to a further aspect of the invention, the first end of theguiding line is connected to a rigid stiffening element secured to theaerodynamic wing, particularly a central stick, and the top of the polepreferably comprises a rigid adapter element adapted to be coupled tothe stiffening element.

This arrangement ensures a safe and rigid docking connection between themasthead and the aerodynamic wing. The course of the guiding linethrough or along the masthead is realized in a way that ensures thestiffening element of the aerodynamic wing to be pulled correctlytowards the adapter element in order to provide a smooth dockingprocess.

The invention may be further improved in that a plurality of reefinglines is located across the aerodynamic wing in order to change theaerodynamic profile or dimension of the aerodynamic wing in a mannerthat aerodynamic properties are changed, e.g. the uplift force isreduced when the reefing lines are hauled in. With this preferredembodiment it is possible to reduce the uplift forces during the landingprocess of the aerodynamic wing. During landing, it is desirable to beable to move the aerodynamic wing easily to its landing position closeto the masthead. Since the aerodynamic wing is dimensioned to create amaximal uplift force during the flying phase, its profile and dimensionmay work against a pulling force trying to pull the aerodynamic wingdownwards and towards the masthead. Thus, it is preferred that theuplift force of the aerodynamic wing is reduced during landingmanoeuvres. This is realized using reefing lines, that reach across thesurface and profile of the aerodynamic wing, preferably in a symmetricpattern in relation to a central stiffening element. These reefinglines, while being hauled in, change the dimension and profile of theaerodynamic wing in a way to reduce the uplift force.

This embodiment can be further improved in that the first end of theguiding line is connected to the plurality of reefing lines to effecthauling in and veering out of the reefing lines via the guiding line.This can be realized for example by merging the reefing lines to oneline that is connected to the guiding line. A connection element may beprovided for connecting the first end of the guiding line to theplurality of reefing lines or to a single line the plurality of reefinglines has merged into.

This embodiment can be further improved in that the plurality of reefinglines is at least partially guided along a stiffening element such as acentral stick secured to the aerodynamic wing. In this way the course ofthe single reefing lines can be organized and handled in a easier way.Also, the connection of the plurality of reefing lines to the guidingline can be realized using the stiffening element.

In order to even better control the reefing lines, a preferredembodiment provides a blocking element preventing hauling in of thereefing lines in a blocking state and allowing hauling in of the reefinglines in a non-blocking state via a load transmission connection betweenthe plurality of reefing lines and the first end of the guiding line.This way, a tensile force can be applied to the guiding line when theblocking element is in a blocking state, without hauling in the reefinglines. This is preferred for example during the flying phase, where nochange in dimension or profile of the aerodynamic wing is desired. Also,during starting and landing phases, it is desirable to actively definethe starting of hauling in of the reefing lines in order to be able tobetter control the movement of the aerodynamic wing. Thus, it might bedesirable, for example during landing, to bring the aerodynamic winginto or close to its landing position via hauling in the guiding lineand only changing the blocking element from its blocking state to itsnon-blocking state when the aerodynamic wing has reached or almostreached its landing position. This way it can be prevented, that theaerodynamic wing is accidentally changed in its profile or dimensionwhile in a position further from its landing position and thus riskingto decrease uplift force and thus lose the aerodynamic wing by wateringit for example.

A further embodiment of the invention is characterized in that the poleis a mast element, particularly a telescope mast and/or a mast having apivotal coupling of the base platform to fold the mast and bring it intoan essentially horizontal orientation. This way it is possible tominimize the vertical extension of the mast during a phase where theaerodynamic wind propulsion device is not used and therefore the mastnot needed. Since the prime area of application of the aerodynamic windpropulsion device is on watercrafts, wind resistance usually is aparameter to be optimized. Thus, while the aerodynamic wind propulsiondevice is not in use, it is desirable to minimize the wind resistanceresulting from the mast. Also, this way it is possible to more easilyreach the top of the mast and the masthead, where the rigid mastheadadapter is located, in case the mast, the masthead, or the mastheadadapter need inspection, overhaul or other measures requiring a closehandling of the mast.

A further preferred embodiment of the invention is characterized in thatthe guiding line is inserted into or attached to the pole at the top,particularly the masthead, and is guided via a pulley. By attaching theguiding line in this manner to the masthead it is possible to pull theaerodynamic wing into a position close to the masthead, which is usuallydesirable for starting and landing the aerodynamic wing. By guiding theguiding line via a pulley it is ensured, that the guiding line can beguided essentially in variable angles in relation to the base platformand to minimize friction at the turning point.

In a further embodiment of the invention the tractive cable is capableof carrying high tensile forces and/or the guiding line is capable ofcarrying low tensile forces, particularly tensile forces of about0.5-3%, in particular 1%, of the tensile forces of the tractive cable.These characteristics are due to the fact, that the main forces createdduring the flying phase by the uplift force of the aerodynamic wing aretransferred to the base platform via the tractive cable, which thereforehas to be capable to carry very high tensile forces. The guiding line onthe other hand is used to control the aerodynamic wing during phaseswhere the aerodynamic wing does not reach its maximal uplift force, sothat the forces resulting in the guiding line will generally be muchlower than the ones in the tractive cable. This relation in forces to becarried also results in a similar relation regarding the dimensions ofthe tractive cable and the guiding line. The guiding line may have amuch smaller diameter than the tractive cable, thus significantlyreducing the weight of the guiding line which is acting onto the wingelement. Also, different materials for the tractive cable and theguiding line might be used.

Still further it is preferred to provide a signal and/or powertransmission, which is included in the guiding line. By this preferredembodiment signals and/or power can be transmitted from the baseplatform to the wing element or vice versa via a signal line and/orpower line included in the guiding line. The signal line and/or powerline may be arranged parallel to the guiding line or coaxial within theguiding line. Including such signal line and/or power line into theguiding line will not effect a significant increase of the weight of theguiding line or the dimensions of the guiding line and hence its windresistance. Thus it will not significantly decrease the power of thewing element for pulling the nautic vessel.

According to a further important preferred embodiment a coupling elementis provided for selectively fixing the guiding line to the steeringunit. Since the guiding line is coupled with its first end permanentlyto the wing element, this may affect the flight attitude of the wingelement and such effect will increase at high altitudes since theguiding line must be veered out and thus the weight of the guiding lineacting onto the wing element will increase. Often, the flight attitudeof the wing element is levelled out by the plurality of lines couplingthe wing element to the steering unit and an additional effect inducedby the guiding line will significantly reduce the power of theaerodynamic wing element and may even result in loss of control. Toovercome these drawbacks the guiding line may be coupled to the steeringunit in such a way that the force induced by the weight of the guidingline not further acts directly onto the wing element but onto thesteering unit. This will reduce or eliminate forces acting onto the wingelement via the guiding line and result in the wing element being loadedonly via the plurality of lines coupling the wing element to thesteering unit. Such selective coupling of the guiding line to thesteering unit may easily be realized by a short line connecting theguiding line at a point which is arranged in a distance from the firstend coupled to the wing element corresponding to the distance betweenthis first end and the steering unit. The short coupling line isconnected to the steering unit in such a way that it can be hauled inand thus pulls the guiding line to the steering unit and fixes itthereto when the coupling line is completely hauled in. Beforeinitiating a landing manoeuvre the coupling line may be veered out toallow a direct pulling force to be exerted to the wing element via theguiding line.

According to another aspect of the invention, the aerodynamic windpropulsion device as mentioned above or described in the introductoryportion of this description may be further improved in that a section ofthe guiding line extends between the base platform and the top of thepole and the pole comprises a tractive device, that is capable ofapplying a tensile force to this section.

Usually, a section of the guiding line extending between the baseplatform and the top of the pole is free of tension while the guidingline is not in use to guide the aerodynamic wing, often resulting inkinks, knots or the like when forces are applied to the guiding line anda movement, particularly a sudden movement, of the guiding line isnecessary. According to the invention the guiding line is constantlyexposed to a low tensile force in this section, the force beingsufficient to keep the guiding line in a tense state and thus preventingthe forming of kinks, knots or the like during hauling in or veeringout.

The application of this concept is not restricted to the guiding linebut can extend to any line, particularly the reefing lines, that may bepulled into or along the mast as well. The advantage of preventing theforming of kinks, knots or the like during hauling in or veering out byproviding a tensile force in a section of the line may be used for anyline of an aerodynamic wind propulsion device.

Another advantage of this embodiment is that a constant tensile force inthe section between the base platform and the top of the pole of theguiding line enables and/or enhances the introduction of a constanttensile force to the guiding line by adjusting the tensile force appliedto the guiding line at its second end corresponding to the tensile forceapplied to the guiding end through the uplift of the aerodynamic wing.

This embodiment of the invention can be further improved in that thetractive device is a pair of tension pulleys arranged opposed to eachother and engaging the guiding line between them, wherein at least oneof the tension pulleys is capable of applying the tensile force via atorque onto the guiding line. The tension pulleys can be located forexample below the pulley at the top of the mast. Tension pulleys applythe tensile force to a cable or line by embracing the cable or linebetween them and being pressed against the cable or line via a springfor example. The tension of the spring and the torque to be applied tothe guiding line have to be adjusted to the dimension and material ofthe cable or line and of the tension pulleys, in order to prevent slipbetween the cable or line and the tension pulleys or to at least preventexcessive wear of the cable or line and the tension pulleys.

The invention can be further improved in that at least one of thetension pulleys is being driven by a driving assembly, wherein thedriving assembly is a rotating field magnet particularly. In order forthe tension pulleys to be able to apply a tensile force via a torqueonto the guiding line, it is preferred that the tension pulleys arebeing driven. A rotating field magnet is a special torque motorapplicable for continuous operation where a torque has to be applied.

This invention can be further improved in that the tension pulleys canbe set to a mode wherein they are free to rotate to follow a movement ofthe guiding line or the tractive cable respectively. Since the guidingline or the tractive cable respectively are subject to veering-out- andhauling-in-movements it is not desirable for the guiding line or thetractive cable, respectively, to be blocked by the tension pulleys.Therefore the tension pulleys are capable to rotate freely while theguiding line or the tractive cable respectively are being veered out orhauled in. Since usually the forces applied to the guiding line duringveering out or hauling in are larger than the tensile force applied tothe guiding line via the torque of the tension pulleys, this force iseasily overcome. Since there is no blocking mechanism of the tensionpulleys, once the higher force for veering in or hauling out is applied,the tension pulleys can rotate freely according to the movement of theguiding line or the tractive cable respectively.

The preferred embodiment can be further improved in that the torqueand/or the tensile force of the tension pulleys can be adjusted,particularly to compensate wear on the tension pulleys or the guidingline or the tractive cable respectively. This adjustment is necessary,since wear or abrasion of either the guiding line or the tractive cablerespectively or the tension pulleys will lead to a lower resultingtensile force in the guiding line or tractive cable respectively given aconstant torque. In the worst case no tensile force is applied and thusthe function of the tractive device does not exist. Since a precisecontrol of the applied forces is necessary for a successful control ofthe aerodynamic wing, it is important to adjust, particularly increase,the applied torque and/or the tensile force between the tension pulleysin order to achieve a resulting tensile force in the guiding line ortractive cable respectively that is constant over time.

According to another aspect of the invention, the aerodynamic windpropulsion device as mentioned above or described in the introductoryportion of this description may be further improved in that the secondend of the tractive cable and/or the second end of the guiding line areconnected to the base platform via at least one winch for veering-outand hauling-in the tractive cable or the guiding line, respectively,wherein the at least one winch is equipped with two operating modes,wherein the first operating mode applying a low force with high speedand the second operating mode applying a high force with low speed.

This way it is possible to adjust the force and speed used duringveering out and hauling in to the current situation. For example, if along section of a line or cable has to be hauled in or veered out, whilethe force resulting from the uplift of the aerodynamic wing is low, itis desired to use an operating mode applying only low force or movingthe line or cable at a high speed. Whereas in a situation, where tensileforces opposing a hauling in are very high, it is preferred to use anoperating mode applying a high force at a low speed.

This embodiment of the invention is preferably improved in that the atleast one winch is connected to one drive unit and said drive unit iscapable of being operated in the two modes two separate drive units, onedrive unit being capable of being operated in the first mode and theother drive unit being capable of being operated in the second mode. Dueto the high forces occurring when using an aerodynamic wind propulsiondevice, it is preferred to use drive assemblies to drive the winches. Inorder to be able to apply different operating modes as described above,a single drive unit either has to comprise two operating modes, that canbe chosen from or switched in between, or two separate drive units areprovided, one for the first mode and one for the second mode.

This embodiment can be further improved in that an aerodynamic windpropulsion device according to the invention, having two separate driveunits, further comprises at least one coupling for selectively couplingone of the two drive units to the at least one winch. If separate driveunits are used to realize the different operating modes, it has to beensured, that the required drive unit is coupled to the winch asrequired to operate in this specific operating mode. If there are twodrive units associated with one winch, a coupling may selectively coupleeither one drive unit or the other to the winch according to therequired operating mode.

In a further aspect, the invention may be embodied in a watercraftcomprising an aerodynamic wind propulsion device as described above. Inthis respect, reference is made to the international applicationsmentioned in the introduction of this description describing suchsystems for towing watercraft.

Further, the invention may be embodied in the use of an aerodynamic windpropulsion device as described above to drive a watercraft.

Further, the invention may be embodied in the use of an aerodynamic windpropulsion device as described above to start, land, fly and/or rescuean aerodynamic wing.

According to a further aspect of the invention a method for controllingan aerodynamic wind propulsion device, as described in the introductorypart of this description is provided, that is characterized by the stepsof connecting a second end of the guiding line is to the base platform,guiding the guiding line through or along the pole during and betweenstarting and landing manoeuvres and managing the tensile force in theguiding line according to different functions of the guiding line atleast during starting and landing manoeuvres.

One advantage of this embodiment is the reduction of reaction time forcontrolling the aerodynamic wing via the guiding line as describedabove. Another advantage is a damping of the movements of theaerodynamic wing and thus an improvement of the controllability of theaerodynamic wing and a smoother starting and landing process.

In a first embodiment it is preferred that the method comprisesadjusting the tensile force applied to the guiding line at its secondend, particularly through a winch connected to the base platform and/ora tractive device located at the pole, corresponding to the tensileforce applied to the guiding line at its first end through the upliftforce of the aerodynamic wing so that a certain tensile force issustained in the guiding line during a guiding phase as part of startingor landing manoeuvres.

This concept is realized by establishing a force equilibrium taking upthe resulting force of the aerodynamic wing, the force applied by thewinch and a predefined initial tension of the guiding line. Bycontrolling the forces applied by the winch this equilibrium can beadapted constantly to changes in the resulting force of the aerodynamicwing, thus keeping the initial tension of the guiding line constant ornear constant with the advantages mentioned above.

Further, it is preferred that the method comprises veering-out andhauling-in the guiding line parallel to the traction cable during aflying phase, wherein little or no tensile force is sustained in theguiding line. For a certain embodiment this may be the case for asituation, where the distance between the steering platform and the baseplatform is about 40 m or more.

It is still preferred to haul-in the guiding line via applying a forceat the second end of the guiding line during landing or in order torescue the aerodynamic wing in a situation of instability. For a certainembodiment this may be the case for the lowest flying zone, where thedistance between the steering platform and the base platform is about 30m or less.

In a further embodiment of the invention it is preferred that during astarting phase the aerodynamic wing is unfolded using a driving assemblywith high force and low speed.

In a further preferred embodiment at least one winch connected to thesecond end of the tractive cable and/or the second end of the guidingline for veering-out and hauling-in the tractive cable or the guidingline respectively is provided, and the at least one winch is operated intwo operating modes, wherein the first operating mode applies a lowforce with high speed and the second operating mode applies a high forcewith low speed. Reference is made to the description of the details andadvantages of two operating modes given above.

A further development of the invention is preferred wherein the winch ofthe guiding line is operated in the first operating mode during theguiding phase, the winch of the guiding line is operated in the secondoperating mode during unfolding and folding of the aerodynamic wing andthe winch of the guiding line is operated in first operating mode or thesecond mode during the rescue manoeuvres. The choice of the operatingmode depends on the circumstances under which the aerodynamic windpropulsion device is operated.

According to another aspect of the invention a method as mentioned aboveor in the introductory portion of this description may be furtherimproved by applying a tensile force to a section of the guiding linethe section being arranged between the base platform and the top of thepole. To this extent, the pole may comprise a tractive device,particularly a pair of tension pulleys arranged opposed to each otherwhich engages the guiding line between them, that is capable of applyinga tensile force, particularly via a torque, onto the guiding line.

In a further embodiment of the invention it is preferred to drive thetractive device by a driving assembly, particularly a rotating fieldmagnet.

Finally it is preferred to adjust the torque and/or the tensile force ofthe tractive device, particularly to compensate wear of the guiding lineor the tension pulleys.

Reference is made to the description of the details and advantages ofthe tractive device, particularly the pair of tension pulleys, givenabove.

Preferred embodiments of the invention shall now be described withreference to the attached drawings, in which

FIG. 1: shows a perspective view of a first embodiment of the deviceaccording to the invention during the flying phase,

FIG. 2: shows a perspective view of the first embodiment of the deviceaccording to the invention during initiating of the guiding phase,

FIG. 3: shows a perspective view of the first embodiment of the deviceaccording to the invention in landing position,

FIG. 4: shows a schematic sectional view of a detail of a secondembodiment of the device according to the invention,

FIG. 5: shows a perspective view of a third embodiment of the deviceaccording to the invention,

FIG. 6: shows a perspective view of the third embodiment of the deviceaccording to the invention in starting and landing condition, and

FIG. 7: shows a schematic view of a detail of a fourth embodiment of thedevice according to the invention.

FIG. 1 shows an aerodynamic wind propulsion device 100 comprising anaerodynamic wing 110 connected to a steering unit 130 located below theaerodynamic wing 110 via a plurality of lines 120, particularly steeringlines and/or fixing lines, a tractive cable 140, wherein a first end 141of the tractive cable is connected to the steering unit 130 and a secondend 142 of the tractive cable is connected to a base platform 170. Theaerodynamic wind propulsion device 100 also comprises a guiding line 150having a first end 151 connected to the aerodynamic wing 110 and a mast160 being connected to the base platform 170, the mast having a masthead161.

The second end 152 of the guiding line is connected to the base platform170 via a winch 163. The guiding line 150 is guided to the masthead 161and runs along the mast 160 towards the winch 163.

The tractive cable 140 is connected with its second end 142 to anotherwinch 143. It can be seen from FIG. 1 that during the flying phase theaerodynamic wing is located high above and generally in front of thevessel 170. Generally, the position of the aerodynamic wing in relationto the vessel 170 depends on wind conditions and other parameters likevessel speed, wave height and others and the wing is driven in certainfigures to increase the tensile force for pulling the vessel. During theflying phase the traction cable 140 transfers the tensile force appliedby the uplift force of the aerodynamic wing 110 to the base platform.The guiding line 150 is connected with its first end 151 to a centralstick 111 disposed within the wing for stiffening the wing element. Atthe front end of the wing, a coupling section of the stick 111protrudes. This coupling section is adapted to be mechanically coupledto the masthead 161. The second end 152 of the guiding line is woundaround the winch 163 that is connected to the base platform 170 so thatthe guiding line is “co-flying” with the tractive cable but is notcarrying any significant tensile force. In order to prevent the“co-flying” guiding line 150 from twisting with other elements, e.g. thetraction cable 140, and in order to reduce reaction time, a smalltensile force is applied to the guiding line 150. This is done byveering out and hauling in the guiding line 150 via the guiding linewinch 163 so far, that a small, preferably constant and predeterminedtensile force remains in the guiding line 150.

FIG. 2 shows the same embodiment as shown in FIG. 1 with the device in aposition where the guiding phase is initiated. As can be seen from FIG.2, the aerodynamic wing 110 is in a position in relation to the vessel170, where the aerodynamic wing has been brought closer to the vessel170 compared to FIG. 1 by hauling in the tractive cable 140. Theremaining length of the tractive cable between the base platform and thesteering unit is only a little longer than the length of the mast 160,as can be seen from FIG. 2. This indicates that the guiding phase is tobe initiated, since the guiding phase preferably starts when theremaining length of the tractive cable 140 between the base platform 170and the steering unit 130 is about the same as the height of the mast160.

The “co-flying” guiding line 150 has been hauled in parallel to thetractive cable 140, but still only carries a very low tensile force, ascan be seen from the flared form of the guiding line 140 in FIG. 2.

To start the guiding phase the tractive cable 140 is further hauled inwhile parallel the guiding line 140 is hauled in until a desired guidingforced is applied to the guiding line 150. This guiding phase iscontinued until the aerodynamic wing has reached its landing position asshown in FIG. 3. During the guiding phase the winch 163 is operated inthe first operating mode, applying a low force with high speed. Only forthe very last section of the guiding line to be hauled-in, particularlya section of a length that equals approximately mast height and dependson the size of the aerodynamic wing, the winch is operated in the secondoperating mode applying a high force with low speed in order to providethe force necessary to dock the central stick of the aerodynamic wing110 to a complementary rigid adapter at the masthead 265.

The landing position as shown in FIG. 3 is characterized by the steeringunit 130 being close to or touching the base platform 170 and thecentral stick 111 secured to the aerodynamic wing is close to orconnected to the complementary rigid adapter element located at themasthead 265. This implies that generally for aerodynamic windpropulsion devices the distance between the steering unit and theaerodynamic wing should be approximately the same as the height of thepole or mast respectively.

The guiding line is coupled to the wing via a plurality of reefing linesarranged within the wing such that pulling the reefing lines reduces thedimension of the wing.

In this position the reefing lines of the aerodynamic wing 110 arehauled in in order to initiate a controlled collapse of the aerodynamicwing so that the guiding line and the reefing lines can be completelyhauled-in and the aerodynamic wing itself can be retrieved. During thisphase the winch 163 is operated in the second operating mode applying ahigh force with low speed.

In FIG. 4 the arrangement of the tension pulleys 262 and the winch 263are presented in a more detailed schematic view. The guiding line 250 isguided via a pulley 268 that is located near the top of the mast 261.Below this pulley 265 a pair of tension pulleys 262 is located. Theguiding line 250 continues through the two tension pulleys 262 a and 262b to the winch 263 that is connected to the base platform 270 and fromthere on to a cable storage means 266, also connected to the baseplatform 270. The tension pulley 262 a is being driven by a rotatingfield magnet (not shown) to apply a tension force via a torque onto thesection 267 of the guiding line, that extends from the winch 263 at thebase platform 270 to the pair of tension pulleys 262 at the top of themast, in order to keep the section 267 of the guiding line under aconstant low tension.

When the guiding line 250 is veered-out or hauled-in using the winch 263the tension pulleys 262 change to a state where they can rotate freelyto accommodate the movement of the guiding line 250 and do not blockthis movement.

FIG. 5 shows a perspective view of a third embodiment of the deviceaccording to the invention, wherein the guiding line 350 is connectedwith its first end 351 to the central stick 311 of the aerodynamic wing310. The guiding line can selectively be fixed to the steering unit 330by a short coupling line 354 connecting a point 353 of the guiding linewhich is arranged in a distance from the first end 351 coupled to theaerodynamic wing 310 which distance approximately corresponds to thedistance between the aerodynamic wing and the steering unit 330. Theshort coupling line 354 is connected to the steering unit 330 in such away that it can be hauled in and thus pulls the guiding line 350 to thesteering unit 330 and fixes it thereto when the coupling line 354 iscompletely hauled into the steering unit. FIG. 5 shows the embodiment ina flight situation, where it is desirable to load the aerodynamic wing310 only via the plurality of lines 320 coupling the aerodynamic wing310 to the steering unit 330. The short coupling line 354 is hauled inas shown in FIG. 5, so that the force induced by the weight of theguiding line 350 does not act directly onto the aerodynamic wing 310 butonto the steering unit 330. During starting and landing manoeuvres thecoupling line 354 may be veered out (not shown) to allow a directpulling force to be exerted to the aerodynamic wing 310 via the guidingline 350.

FIG. 6 shows a perspective view of the third embodiment of the deviceaccording to the invention in the starting and landing condition. Asshown, the guiding line 350 is now directly acting via its first end 351onto the aerodynamic wing whereas the coupling line 354 is veered out toavoid load transmission from the guiding line to the steering unit 330.The first end 351 of the guiding line thus is fixed to the central stick311. The second end 352 of the guiding line is fixed to the baseplatform 370 via a winch 363. The coupling line 354 is connected to theguiding line 350 via a slidable element 355 which can slide along theguiding line. The sliding movement between the guiding line and theslidable element 355 can be blocked when the coupling line 350 iscompletely hauled in and thus the guiding line 340 is connected to thesteering unit 330. This will prevent a direct pulling force to beexerted to the aerodynamic wing 310 via the guiding line 350.

Alternatively, the coupling line 354 can be connected to the guidingline 350 at a defined fixing point. In this case the length of thesection of the guiding line between the fixing point of the couplingline 354 and the central stick 311 must have at least the length of thedistance between the central stick 311 and the steering unit 330.

FIG. 7 shows a schematic view of a detail of a fourth embodiment of thedevice according to the invention. A winch 510 is connected to a firstdrive unit 520 and to a second drive unit (not shown) via a coupling 530for selectively coupling one of the two drive units to the winch 510. InFIG. 7 the first drive unit 520 is coupled via the coupling 530 to thewinch 510. The first drive unit 520 is capable of being operated in afirst mode that applies a low torque with high speed to the winch 510when the winch 510 is coupled via the coupling 530 to the first driveunit and the winch 510 thus applies a low force with high speed to aline (not shown) associated with the winch. The second drive unit (notshown) is capable of being operated in a second mode that applies a hightorque with low speed to the winch 510 when the winch 510 is coupled viathe coupling 530 to the second drive unit and the winch 510 thus appliesa low force with high speed to a line (not shown) associated with thewinch.

1. An aerodynamic wind propulsion device, particularly for watercrafts,comprising an aerodynamic wing being connected to a steering unitlocated below the aerodynamic wing via a plurality of lines,particularly steering lines and/or tractive lines, a tractive cable,having a first end of the tractive cable connected to the steering unitand a second end of the tractive cable connected to a base platform, theaerodynamic wing having an aerodynamic profile which generates an upliftforce in the direction of the traction cable when the airflow directionis about perpendicular to the tractive cable, a guiding line having afirst end connected to the aerodynamic wing or to the steering unit, apole being connected to the base platform, particularly a mast with ahead on top, the pole serving as a docking point for the aerodynamicwing during starting and landing, characterized in that a second end ofthe guiding line is connected to the base platform during and betweenstarting and landing maneuvers wherein the guiding line is guidedthrough or along the pole and is capable of transferring a tensile forceonto the aerodynamic wing at least during starting or landing.
 2. Anaerodynamic wind propulsion device according to claim 1, wherein thefirst end of the guiding line is connected to a rigid stiffening elementsecured to the aerodynamic wing, particularly a central stick, and thetop of the pole preferably comprises an adapter element adapted tomechanically be coupled to the stiffening element.
 3. An aerodynamicwind propulsion device according to claim 1, characterized in that aplurality of reefing lines is located across the aerodynamic wing inorder to change the aerodynamic profile or dimension of the aerodynamicwing in a manner that aerodynamic properties are changed, e.g. theuplift force is reduced when the reefing lines are hauled in.
 4. Anaerodynamic wind propulsion device according to claim 3, characterizedin that the first end of the guiding line is connected to the pluralityof reefing lines to effect hauling-in via the guiding line.
 5. Anaerodynamic wind propulsion device according to claim 4, characterizedin that the plurality of reefing lines is at least partially guidedalong a stiffening element such as a central stick secured to theaerodynamic wing.
 6. An aerodynamic wind propulsion device according toclaim 5, characterized in a blocking element preventing hauling-in ofthe reefing lines in a blocking state and allowing hauling-in of thereefing lines in a non-blocking state via a load transmission connectionbetween the plurality of reefing lines and the first end of the guidingline.
 7. An aerodynamic wind propulsion device according to claim 1,characterized in that the pole is a mast element, particularly atelescope mast and/or a mast having a pivotal coupling to the baseplatform to fold the mast and bring it into an essentially horizontalorientation.
 8. An aerodynamic wind propulsion device according to claim1, characterized in that the guiding line is inserted into the pole atthe top, particularly the mast head, and is guided via a pulley.
 9. Anaerodynamic wind propulsion device according to claim 1, wherein thetractive cable is capable of carrying high tensile forces and/or theguiding line is capable of carrying low tensile forces, particularlytensile forces of about 0.5-3%, in particular 1%, of the tensile forcesof the tractive cable.
 10. An aerodynamic wind propulsion deviceaccording to claim 1, wherein a signal transmission line and/or a powertransmission line is included in the guiding line.
 11. An aerodynamicwind propulsion device according to claim 1, characterized by a couplingelement for selectively fixing the guiding line to the steering unit.12. An aerodynamic wind propulsion device according to claim 1, whereina section of the guiding line extends between the base platform and thetop of the pole and wherein the pole comprises a tractive device, thatis capable of applying a tensile force to this section.
 13. Anaerodynamic wind propulsion device according to claim 12, wherein thetractive device is a pair of tension pulleys arranged opposed to eachother and engaging the guiding line between them, wherein at least oneof the tension pulleys is capable of applying the tensile force via atorque onto the guiding line.
 14. An aerodynamic wind propulsion deviceaccording to claim 13, wherein at least one of the tension pulleys isbeing driven by a driving assembly, wherein the driving assembly is arotating field magnet particularly.
 15. An aerodynamic wind propulsiondevice according to claim 14, wherein the tension pulleys can be set toa mode wherein they are free to rotate to follow a movement of theguiding line or the tractive cable respectively.
 16. An aerodynamic windpropulsion device according to claim 13, wherein the torque and/or thetensile force of the tension pulleys can be adjusted, particularly tocompensate for wear on the tension pulleys or the guiding line or thetractive cable respectively.
 17. An aerodynamic wind propulsion deviceaccording to claim 1, wherein the second end of the tractive cableand/or the second end of the guiding line, only when referring to claim1, are connected to the base platform via at least one winch forveering-out and hauling-in the tractive cable or the guiding linerespectively, characterized in that the at least one winch is equippedwith two operating modes, wherein the first operating mode applies a lowforce with high speed and the second operating mode applies a high forcewith low speed.
 18. An aerodynamic wind propulsion device according toclaim 17, characterized in that the at least one winch is connected toone drive unit and the said drive unit is capable of being operated inthe two modes or two separate drive units are provided, one drive unitbeing capable of being operated in the first mode and the other driveunit being capable of being operated in the second mode.
 19. Anaerodynamic wind propulsion device according to claim 18, having twoseparate drive units; further comprising at least one coupling forselectively coupling one of the two drive units to the at least onewinch.
 20. A watercraft comprising an aerodynamic wind propulsion deviceaccording to claim
 1. 21. The use of an aerodynamic wind propulsiondevice according to claim 1 to drive a watercraft.
 22. The use of anaerodynamic wind propulsion device according to claim 1 to start, land,fly and/or rescue an aerodynamic wing.
 23. A method for controlling anaerodynamic wind propulsion device, particularly for watercrafts,comprising the steps of connecting an aerodynamic wing to a steeringunit located below the aerodynamic wing via a plurality of lines,particularly steering lines and/or tractive lines, connecting a firstend of a tractive cable to the steering unit and a second end of thetractive cable to a base platform, connecting a first end of a guidingline to the aerodynamic wing or to the steering unit, providing a polebeing connected to the base platform, particularly a mast with a head ontop, serving as a docking point for the aerodynamic wing during startingand landing, steering the flight of the aerodynamic wing via thesteering unit, characterized by the steps connecting a second end of theguiding line to the base platform, guiding the guiding line through oralong the pole during and between starting and landing maneuvers,managing the tensile force in the guiding line according to differentfunctions of the guiding line at least during starting and landingmaneuvers.
 24. A method according to claim 23, characterized by the stepof adjusting the tensile force applied to the guiding line at its secondend, in response to the tensile force applied to the guiding line at itsfirst end, through the uplift force of the aerodynamic wing so that acertain tensile force is sustained in the guiding line during a guidingphase as part of starting or landing maneuvers.
 25. A method accordingto claim 23, characterized by the step of veering-out and hauling-in theguiding line parallel to the traction cable during a flying phase,wherein little or no tensile force is sustained in the guiding line. 26.A method according to claim 23, characterized by the step of hauling-inof the guiding line via applying a force at the second end of theguiding line during landing or in order to rescue the aerodynamic wingin a situation of instability.
 27. A method according to claim 23,characterized in that during a starting phase the aerodynamic wing isunfolded using a driving assembly with high power and low speed.
 28. Amethod according to claim 23, characterized by the steps of providing atleast one winch connected to the second end of the tractive cable and/orthe second end of the guiding line for veering-out and hauling-in thetractive cable or the guiding line respectively, operating the at leastone winch in two operating modes, wherein the first operating modeapplies a low force with high speed and the second operating modeapplies a high force with low speed.
 29. A method according to claim 28,wherein the winch of the guiding line is operated in the first operatingmode during the guiding phase, the winch of the guiding line is operatedin the second operating mode during unfolding and folding of theaerodynamic wing and the winch of the guiding line is operated in firstoperating mode or the second mode during the rescue maneuvers.
 30. Amethod according to claim 23, characterized by the step of applying atensile force to a section of the guiding line between the base platformand the top of the pole wherein the pole comprises a tractive device,particularly a pair of tension pulleys arranged opposed to each otherand engaging the guiding line between them, that is capable of applyinga tensile force, particularly via a torque, onto the guiding line.
 31. Amethod according to claim 30, characterized by the step of driving thetractive device by a driving assembly, particularly a rotating fieldmagnet.
 32. A method according to claim 30, characterized by the step ofadjusting the torque and/or the tensile force of the tractive device,particularly to compensate for wear of the guiding line or the tensionpulleys.
 33. A method according to claim 23, characterized in thatsignals and/or power are transmitted via a signal line and/or a powerline included in the guiding line.
 34. A method according to claim 23,characterized in that the guiding line is fixed to the steering unit atleast between starting and landing of the wing.